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arXiv · 1904.00399

Excited $B_{c}$ States via Continuum QCD

Lei Chang·Muyang Chen·Yu-xin Liu
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Abstract

We study the most recently observed excited $B_{c}$ states with the Dyson-Schwinger equation and the Bethe-Salpeter equation approach of continuum QCD. The obtained $M_{B^+_{c}(2S)}=6.813(16)\text{GeV}$, $M_{B^{*+}_{c}(2S)}=6.841(18)\text{GeV}$ and the mass splitting $M_{B_c^+(2S)}-M^{\text{rec}}_{B_c^{*+}(2S)} \approx 0.039 \text{GeV}$ agree with the observations very well. Moreover we predict the leptonic decay constant $f_{B^+_{c}(2S)}=-0.165(10)\text{GeV}$, $f_{B^{*+}_{c}(2S)}=-0.161(7)\text{GeV}$ respectively.

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Lei Chang, Muyang Chen, Yu-xin Liu. 2019-03-31. Excited $B_{c}$ States via Continuum QCD. https://doi.org/10.1103/physrevd.102.074010

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